Resilient mounting for chair backs



Dec. 15, 1953 CRAMER 2,662,586

RESILIENT MOUNTING FOR CHAIR BACKS Filed July 28, 1950 2 Sheets-Sheet l INVENTOR.

ec 15, 1953 R. A. CRAMER 2,662,586

RESILIENT MOUNTING FOR CHAIR BACKS Filed July 28, 1950 2 Sheets-Sh t 2 52 v INVENTOF Pay A. Cramer' Patented Dec. 15, 1953 UNITED STATES PATENT OFFICE RESILIENT MOUNTING FOR CHAIR BACKS Roy A. Cramer, Kansas City, Mo. Application July 28, 1950, Serial No. 176,409

4 Claims.

This invention relates to posture chairs, and more particularly to a resilient mounting for the back of such chairs.

The principal object of the present invention is to provide a chair of this type having a back adjustable with respect to the seat portion of the chair and the resilient mounting of the back, so that when backward pressure is placed on the back portion it will move irrespective of the seat portion.

Other objects of the present invention are an angle back member having horizontal and vertical arms; to provide a framework on the standard of the chair having a channel member pivotally mounted therein adapted to receive the horizontal arm of the back of the chair, so that when backward pressure is placed on the back, the vertical arm of the back will move downwardly while the seat portion remains in horizontal position; to provide for resilient mounting of the arm of the back member in the framework structure; to provide adjustment of the tension on the resilient member; to provide for adjustable mounting of the back member on the vertical arm of said member; to provide means for mounting the back member on the vertical arm so that the back member will automatically adjust itself to the back of the user; to provide for mounting of a seat member on the framework structure of the seat portion; to provide means for retaining the horizontal arm of the back member in engagement in said channel of the framework structure and adjustment of said arm with respect to the seat portion forwardly or backwardly; to provide a resilient bumper member around the periphery of said seat member at the lower edge thereof; and to provide a device of this character simple, economical to manufacture, and eficient in operation.

In accomplishing these and other objects of the invention, I have provided improved details of structure, the preferred forms of which are shown in the accompanying drawings wherein:

Fig. l is a perspective view of the chair embodying the features of my invention.

Fig. 2 is a side view of the chair.

Fig. 3 is a cross-sectional view taken on line 33, Fig. 2.

Fig. 4. is a cross-sectional view through the chair particularly illustrating the framework structure and resilient mounting of the back member of the chair.

Fig. 5 is a perspective view of the framework structure mounted on the standard. d

Fig. 6 is a view partly in cross-section particu- 2 larly illustrating the back member in tension against the resilient mounting thereof.

Fig. 7 is a cross-sectional view taken on the line 1-1, Fig. 4.

Referring more in detail to the drawings:

I designates a chair embodying the features of my invention comprising a standard 2 provided with a hub 3 to which is attached a plurality of legs ti provided with casters 5, forming a base for the chair. The hub 3 has a depending sleeve portion 6 provided with a boss 1 having a locking member 8 including a pin 9 adapted to engage in recesses ID in the standard 2 for adjusting the height of the chair.

The locking member includes a lever H pivotally mounted on the end of the pin 9 and a spring as indicated at ll, the lever H having ears or the like I3 and a cam portion engaging the end of the boss as indicated at I i for releasing the pin from the recesses for movement of the sleeve member with respect to the standard.

The upper end of the standard 2 is rounded as indicated at i5 (Fig. 4) and adapted to engage over the top of the standard [5 is a framework structure 16 having a centrally bored depending boss ll, the upper end of the centrally bored portion forming a bearing for the rounded end it of the standard. An annular groove I8 is provided near the upper end of the standard and the depending boss is transversely bored and adapted to receive the threaded shank of a pin 19 having its inner end engaging in the annular groove for retaining the framework structure on the standard.

The framework structure It extends outwardly from the depending boss I! forming a front portion 2i) and the rear portion 2|. The framework consists of a substantially elongated plane surface 22 turned upwardly forming sides as indicated at 23. The front portion is flared outwardly and upwardly forming laterally extending flanges 2i and 25 and bosses 2e and 2! with a recess 22 therebetween. The rear portion of the framework is provided with laterally extending flanges 29 and 30 which, together with the flanges 211 and 25, form a mounting for a seat 3|, the seat being secured to the framework by bolts or set screws engaging in the openings 32 and 33 in the flanges and through the opening 35 in the bosses 2i.

Spaced from the flanges 24 and 25 are upstanding ears 36 and 37 to which is attached a channel member 38 which is pivoted to the ears by pins or the like 39. The channel member has sides and 4! and is provided at its rear end with a cross pin '42 spaced from the bottom 43 of the 3 channel member and the extreme rear end is provided with a depending recess portion 44 in which is mounted a cross pin 45.

A back member 46 is provided for attachment to the framework structure and consists of an angle member having a vertical arm 41 and a horizontal arm 48. The horizontal arm 48 is adapted to engage in the channel way 49 of the channel member 38 with its inner end 58 extending substantially to the front of the framework structure, the upperface of arm 48 engaging the underside E8 of a U-shaped member 49' securely attached to and depending from the underside of the seat into the channel Way 49 as best shown in Fig. '7. The arm 48 engages under thepin 42 and over the pin 45 of the channel member 38, as best illustrated in Figs. 4 and 6. The front portion of the framework structure is provided with a threaded bore opening adapted to receive the threaded shank of a pin 52 having a hand portion 53 for retaining the horizontal arm of the back member in the channel member 38 and provide for adjustment of said'arm forwardly orbackwardly with respect to the seat portion 3 I.

The vertical arm 41 of the back member supports a back rest 54 comprising a frame 55 pivotally secured to a sleeve member 56 by a pin 51. The sleeve 56 engages overthe upper end of the arm a? and is adjustable thereon by a hand pin 53 having a threaded shank 59 extending through a threaded opening 58 in the lower end of the sleeve as best illustrated in Fig. 4. The sleeve has forwardly extending ears 6| to which the frame 55 is attached by the pin 51 and the sleeve is provided with bosses 62 and 63 adapted to receive the ends of coiled springs 6 and 85 having their opposite end engaging against the frame 55 of the back member 54 as best illustrated in Fi 4, so as to provide a fulcrum for the back member to fit the back of the user when the back is either in a forward or backward position. The back rest proper consists of a resilient padding such as foam latex or th like 66 having a cover 61 removably attached thereto as indicated at (58.

The seat 3| comprises a base 69 having threaded openings'for receiving the pins or set screws for attachment of the seat to the framework structure as above indicated. The base is also provided with openings H to allow for movement of air to :and from a resilient pad member 72 composed of foam latex or the like which'is held thereon by a removable cover '73 and a resilient bumper 'Mengaging in a groove around th frame 69 of the seat.

The rear end of the framework structure is provided with a substantially circular depending housing 76 having a bottom '11 provided with an opening i8 adapted to receive a threaded pin 19 provided with a handportion 80. The rear side of the housing is provided with a slot 8| adapted to receive a lug 82 of a threaded washer 83 tapped on the threaded pin 19 in the housing. A coil spring 84 surrounds the pin 19 and has its lower end engaging against the washer 83 and its upper end engaging a boss 85 depending from the underside of the channel member 38 pivoted in the framework structure. Turning of the hand of the threaded pin 18 will adjust tension of the spring Mbymovement of the washer upwardly or downwardly'in the housing it, the lug S2 preventing the washer from turning and the washer is provided with an annular groove 86 so as to retain the coil spring therein,

as best illustrated in Fig. 4. The hand member 88 is secured to the end of the pin 18 by a set screw 81. If desired the housing 16 may be provided with indicia near the slot 8| to indicate the tension on the spring 84. The upper end of the threaded pin 19 is provided with a rubber bumper as indicated at 88 to absorb any shock if the boss should contact the end of said pin.

In operation of a chair constructed and assembled as described, the height of the seat from the floor is adjusted by manipulation of the lever l l and movement of'the standard 2 in the sleeve member 6. The horizontal arm 48 of the back zmember 46 is adjusted forwardly or backwardly cal arm '41 by manipulation of the hand screw 58-.and movement of the sleeve member on the back of the vertical arm portion 41. Backward pressure on the back rest .54 will cause the .back to fulcrum on the sleeve member and assume the position best fitted to the back when in different positions and will also cause the horizontal arm of the back member to be lowered against tension of the spring 84 and assume th position shown in Fig. 6, the vertical arm extending-backwardly at an angle and the horizontal arm bending downwardly due to pivoting of the channel member 38 in the framework structure as above described.

It will be obvious from the foregoing that I have provided an improved posture chair having a resiliently mounted back member easily a'djustable to accommodate the user.

What I claim and desire to secure by Letters Patent is:

1. A resilient mounting. for a back for a chair having asupport and a channel-shaped frame member having portions extending forwardly and rearwardly of saidsupport including,.a channel member .pivotally mounted to said frame forwardly of said support, a'pin extending transversely across said channel-shaped member rearwardly of the support and spaced .from the bottom thereof, a housing depending from the rearwardly extending portionof the frame, a coil spring in sai'dhousingihaving its upper end engaging against the lower side of said channel member, means for adjusting the tension of said spring in saidhousingsaidchair back including an angle-shaped arm having its horizontal portion engagingin said channel member underneath said cross .pin, and means adjustably securing the horizontal portion of said arm in saidfirst "named channel member whereby'back pressure on said back member will .cause the channel member to be urged. against the spring tension of said spring and the cross pin preventing .movement of the arm upwardly.

2. A resilient mounting for a back for a chair having a support and a channel-shaped frame member having portions extendingforwardly and rearwardly of said support including, a channel member pivotally mounted to said .frame .forwardly of said support, a .pin extending transversely across said channel-shaped. member and spaced from the bottom thereof, the rear end of said channel-shaped member having a depending recess portion, a pin mounted in saidrecesslportion, a housin depending from the rearwardly extending portion 'of the frame, said channel member having a depending boss in alignment with the dependinghousing' in said framepa coil spring in sai'd housing having itsupper'endengaging said boss, means for adjusting the tension of said spring in said housing, said chair back including an angle-shaped arm having its horizontal portion engaging in said channel member underneath said cross pin and over said pin in the recess portion thereof, and means at the forward end of said frame and engaging said arm adjustably securing the horizontal portion of said arm in said channel member whereby back pressure on said back member will cause the channel member with the horizontal arm of said back member to be urged against the spring tension of said spring and the arm will be tensioned near its forward end and the cross pin preventing movement of the arm upwardly.

3. A resilient mounting for a back for a chair having a support and a channel-shaped frame member for a seat having portions extending forwardly and rearwardly of said support including, a channel member pivotally mounted to said frame forwardly of said support, a pin extending transversely across said channel-shaped member and spaced from the bottom thereof, the rear end of said channel-shaped member having a recessed portion, a pin mounted in said recess portion, said seat having a U-shaped channel member engaging in said channel member forwardly of said first named pin, a housing depending from the rearwardly extending portion of the frame, said channel member having a depending boss in alignment with the depending housing on said frame, a coil sprin in said housing having its upper end engaging said boss, means for adjusting the tension of said spring in said housing, said chair back including an angle-shaped arm having its horizontal portion engaging in said first named channel member underneath said cross pin and over said pin in the recess portion thereof, and means at the forward end of said frame and engaging said arm adjustably securing the horizontal portion of said arm in said first named channel member whereby back pressure on said back member will cause the first-named channel member with the horizontal arm of said back member to be urged against the sprin tension of said spring and the arm Will be tensioned near its forward end and the cross pin preventing movement of the arm upwardly.

4. A resilient mounting for a back for a chair having a support and a channel-shaped frame member having portions extending forwardly and rearwardly of said support including, a channel member pivotally mounted to said frame forwardly of said support, a pin extending transversely across said channel-shaped member rearwardly of the support and spaced from the bottom thereof, a housing depending from the rearwardly extending portion of the frame, a coil spring in said housing having its upper end engaging against the lower side of said channel member, means for adjusting the tension of said spring in said housing, said chair back including an angle-shaped arm having its horizontal portion engaging in said channel member underneath said cross pin, means adjustably securing the horizontal portion of said arm in said first named channel member, a back rest on the upper end of the vertical portion of the angle-shaped back member, and means for pivotally and yieldably mounting said back rest on said vertical portion of the back member, whereby back pressure of the user on the back rest will cause the horizontal arm to move the first-named channel member against the tension of said spring and the back rest to change position conforming to such movement.

ROY A. CRAMER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 899,504 Bolens Sept. 29, 1908 2,054,557 Cramer et a1. Sept. 15, 1936 2,105,510 Smith Jan. 18, 1938 2,208,561 Jung Bauer July 23, 1940 2,410,871 Fields et a1 Nov. 12, 1946 2,524,624 Cramer Oct. 3, 1950 2,547,455 Freeman Apr. 3, 1951 FOREIGN PATENTS Number Country Date 124,229 Austria Aug. 25, 1931 

